This is a proposal for an NIH Biotechnology Resource Center (BRC) located in the MIT Spectroscopy Laboratory to support research in the field of lasers in medicine. It is part of a proposed collaborative program entitled, "Therapeutic Laser-Tissue Interaction Project". The other portion, designed as a Program Project, is entitled "Laser Tissue Interaction Studies" and consists of six interrelated research projects. The proposed BRC will function in association with the MIT Laser Research Center (LRC), an NSF supported Regional Instrumentation Facility which contains one of the largest collections of lasers for basic research in the US, and will be administered by the MIT Spectroscopy Laboratory. Over the past four years about 150 projects have been carried out at the LRC in areas of chemistry, physics, biology and biochemistry, engineering and applied sciences, and medicine. Of these, about 15% are relevant to programmatic objectives of the NIH. This grant application proposes to enlarge the present facilities, staff and activities in five catagories: (1) core research and development will occur in three areas, (a) development of a facility containing new tunable infrared laser sources for use in various types of heating and ablation studies, (b) development of CARS, LIF and Raman spetral diagnostic techniques for tissue identification and probes of temperature and constituents, and (c) study of tissue ablation produced by visible and infrared laser radiation, designed to establish more effective means for surgical and microsurgical tissue removal; (2) collaborative research will occur with the six research projects of the program; (3) projects of outside researchers will be supported using existing and new facilities and staff; (4) training and education will be provided through hands-on laboratory experience, bi-weekly "Seminars in Lasers in Medicine", and annual workshop-minicourse programs; (5) dissemination of information will occur through our quarterly publication, "The Spectrograph". Three new laboratories for medical research will be established. The existing resources of the Center, as well as the proposed new facilities, will be available to collaborative and outside researchers. The organizational structure of the LRC already meets the BRC guidelines and will enlarged to accommodate the increased level of activity.